This is another story like Mission for Duh where I don't need to tell you what happens because you can see for yourself. If they look too small for you to read then you should be able to click on them to see them bigger.
This story has Jamie and Zoe in it and by the end of the first page they have been in it more than Companions have been in any of the stories so far. Jamie has already made himself useful by stating the obvious to the Doctor.
Zoe expressed an interest in Dr Vane so the Doctor tells her to stay behind. This must be because the Doctor likes Jamie more. He's not the only one.
Going by the pictures on this page it looks like Jamie is being played by Professor Brian Cox, instead of Frazer Hines or Hamish Wilson.
And going by what Dr Vane says it may be that Patrick Troughton is playing Dr Who instead of Peter Cushing. I mean that Peter Cushing would normally play Dr Who, not that Patrick Troughton would normally play Peter Cushing. Oh, now I am a confused cat.
This story has gone from pink to blue and now back to pink again, just like Mission for Duh did. I don't know why it has done this, maybe it is just to keep things interesting and be unpredictable? Or maybe it is a story's equivalent of being stripey, like I am?
The tree hasn't done much vampiring yet, and the story's nearly finished!
... and blue again for the last page.
It is indeed "incredible that the solution was so simple." This is not one of the best stories I have read. Cthulhu told me he likes some of it, but even he agrees with me that the ending is not up to much.